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instance method

StringScanner#peek

(::Integer) -> ::String

peek(length) → substring

static VALUE
strscan_peek(VALUE self, VALUE vlen)
{
    struct strscanner *p;
    rb_len_t len;

    GET_SCANNER(self, p);

    len = NUM2LEN(vlen);
    if (EOS_P(p))
        return str_new(p, "", 0);

    len = minl(len, S_RESTLEN(p));
    return extract_beg_len(p, p->curr, len);
}

Returns the substring string[pos, length]; does not update match values or positions:

Example

scanner = StringScanner.new('foobarbaz')
scanner.pos = 3
scanner.peek(3)   # => "bar"
scanner.terminate
scanner.peek(3)   # => ""

See also #named_captures #peek_byte #matched_size #pointer also in 4.0 · 3.4 · 3.3 · 3.2 · 3.1 · 3.0

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